Posted on 06/12/2006 9:20:11 PM PDT by NormsRevenge
MOUNT MERAPI, Indonesia - Mount Merapi's unstable lava dome has partially collapsed, easing pressure that threatened to make the Indonesian volcano erupt.
However, the mountain remains as the "highest possible alert," volcanologist Antonius Ratdomopurbo said on Monday.
"We should know within two days whether we can lower the (alert) level," Ratdomopurbo said.
The mountain has been venting steam and debris for weeks, but its lava dome swelled after a powerful May 28 earthquake, raising concerns the dome could suddenly collapse, sending scalding gas, rocks and debris hurtling into populated areas.
A huge, superheated cloud, the largest this year, brought down a section of the dome on Friday and created a new crater, relieving pressure on the dome.
"Now that the magma can flow out into the new crater, the dome will become much more stable," Ratdomopurbo said.
But he warned that 250,000 beleaguered villagers near Merapi were not yet in the clear, as a crack in the lava dome's southern foot had widened, threatening to unleash more powerful surges of superheated gas.
He said Friday's explosion reduced the dome's height from 380 feet to 305 feet, while its volume dropped to 116 million cubic feet from 140 million cubic feet.
A pyroclastic flow — a fast-moving burst of blistering gases and rock fragments — is the main concern. One killed more than 60 villagers in 1994.
As the volcano smoldered above them, defiant residents of its lower slopes have returned from refugee camps to tend to their normally lush green fields, now coated with gray ash.
Men in conical bamboo hats slammed hoes into Merapi's dark, fertile soil. An ash-covered woman swept gray soot from foliage before hacking it down to feed her livestock.
"I am unafraid. I believe the hot cloud will not attack us," said Suno Sudaraso, who refused to evacuate during last week's eruption. "My four cows will die if I don't feed them. They are my life."
The 9,700-foot Merapi is notoriously unpredictable, and scientists say they don't know for sure if a major eruption is imminent.
About 1,300 people died when it erupted in 1930.
____
Associated Press writer Niniek Karmini contributed to this report.
There's a book called "Volcano Cowboys" about the USGS and Mt. St. Helens, Pinatubo, and I think Nevado del Ruiz in Columbia, and about their prediction attempts, etc.
They had the easiest time at Pinatubo because it was easy to get the Air Force leadership to understand the science involved, because of their educational background.
http://www.drgeorgepc.com/TsunamiMegaEvaluation.html
A good article about the collapse megatsunami threat....
There are some serious problems with the modeling of the La Palma waves...and this guy isn't the only guy that has pointed this out...
But the media (And crappy cable science documentaries) consistently ignore the doubters and present a sensationalized one-sided story.
I recall from the video that one of the real concerns they had was if their prediction didn't pan out. The locals who evacuated would not the next time and there would be a tremendous loss of life. The volcano blew just at the end of the warning period, just before people would have been going back to their villages.
Probably, the military bases had some impact because if they were moving out, it would cause the locals to think twice. It's been a long time since I've watched it; I'll have to plug it in again. It was so good that a college geology professor friend of mine borrowed it to show his classes.
As with most 'good science' the offering of counter theories is useful and generally leads to better understanding. I read the link ... thanks for the alternate view. The Lituya Bay collapse was from an altitude and of a mass capable of transferring a huge amount of energy directly to wave propagation. It appears the La Palma mass isn't arranged so precariously, but I'll keep reading up on it.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.